cmake_minimum_required(VERSION 3.18)
project(cpp_tracker LANGUAGES CXX)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

# Look for existing LibTorch installation (for systems with PyTorch already installed)
list(APPEND CMAKE_PREFIX_PATH "/usr/local/libtorch" "$ENV{HOME}/libtorch")

# Find dependencies
find_package(Torch REQUIRED)

message(STATUS "Found LibTorch: ${TORCH_LIBRARIES}")

# Determine whether to use CPU-only or CUDA implementation
option(CPU_ONLY "Build without CUDA support" TRUE)

if(CPU_ONLY)
    message(STATUS "Building in CPU-only mode")
    add_definitions(-DCPU_ONLY)
else()
    message(STATUS "Building with CUDA support")
endif()

# Define source files for the libraries
set(BB_REGRESSOR_SOURCES
    cimp/bb_regressor/bb_regressor.cpp
)

set(CLASSIFIER_SOURCES
    cimp/classifier/classifier.cpp
)

# Create static libraries
add_library(bb_regressor STATIC ${BB_REGRESSOR_SOURCES})
add_library(classifier STATIC ${CLASSIFIER_SOURCES})

# Set include directories
target_include_directories(bb_regressor PUBLIC 
    ${CMAKE_CURRENT_SOURCE_DIR}/cimp
    ${CMAKE_CURRENT_SOURCE_DIR}/cimp/bb_regressor/prroi_pooling
    ${CMAKE_CURRENT_SOURCE_DIR}/ltr/external/PreciseRoIPooling/pytorch/prroi_pool/src
)
target_include_directories(classifier PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/cimp)

# Link with LibTorch
target_link_libraries(bb_regressor PRIVATE ${TORCH_LIBRARIES})
target_link_libraries(classifier PRIVATE ${TORCH_LIBRARIES})

# Create the demo executable
add_executable(tracking_demo cimp/demo.cpp)

# Link the demo with the libraries
target_link_libraries(tracking_demo PRIVATE bb_regressor classifier ${TORCH_LIBRARIES})

# Copy the executable to the binary directory
install(TARGETS tracking_demo DESTINATION bin)

# Print some info during the build
message(STATUS "LibTorch found at: ${TORCH_INCLUDE_DIRS}")
if(CPU_ONLY)
    message(STATUS "Using CPU-only build")
else()
    message(STATUS "Using CUDA-enabled build")
endif()